Sheet metal lock nut



N 1946- R. a. OLSON, JR

' SHEET METAL LOCK NUT 2 Sheets-Sheet 1 Filed July 22. 1944 (Ittomeg s 2Sheets-Sheet 2 Nov. 12, 1946.

R. G. OLSON, JR

SHEET METAL LOCK NUT Filed .July 22, 1944 Patented Nov. 12, 1946 UNITEDSTATES PATENT OFFICE 2,410,995 SHEET METAL LOCK NUT Raymond G. Olson,Jr., Chevy Chase, Md.

Application July 22, 1944, Serial No. 546,116

4 Claims. 1

This invention pertains to an improved deformable sheet metal lockwasher and the method of making the same, and has as its primary objectthe production of a highly eflicient lock nut simply and cheaply.

Having stated the broad objectives of the invention other objects, novelfeatures of construction and improved operation of the device willappear from the following specific description when read in the light ofthe accompanying drawings illustrating embodiments of lock nutsincorporating the improved inventive concept.

In the drawings:

Fig. 1 is a plan view of a sheet metal blank from which a lock nutembodying the present invention is formed. D

Fig. 2 is a vertical sectional view through a lock nut formed from theblank illustrated in Fig. 1

Fig. 3 is a vertical sectional view of the lock nut as applied to athreaded bolt.

Fig. 4 is a vertical sectional view similar to Fig. 3 the nut havingbeen tightened down to deform the side walls thereof.

Fig. 5 is a top plan view of a filler block or disc suitable for usewith the nut illustrated in Figs. 2 to 4 inclusive.

Fig. 6 is a vertical sectional view similar to Fig. 3 with the fillerblock or disc within the nut.

Fig. 7 is a perspective view of a modified form of lock nut.

Fig. 8 is a perspective view of the insert used with the nut of Fig. 7.

Fig. 9 is a vertical sectional view of the nut appearing in Fig. 7 asapplied to a threaded bolt.

Fig. 10 is a vertical sectional view similar to Fig. 9 the nut beingillustrated as tightened down.

to deform the side walls thereof.

.Describing and having reference to the constr'uctions illustrated inFigs. 1 to 4 inclusive, A designates a stamping from a blank or piece ofsheetmetal which is of adeformable nature and is susceptible of beingbent or deformed without breakage. portion I having therein a centralopening 2 which is adapted to be internally threaded as indicated at 3in 2 of the drawings. A plurality of arms B extend radially from themarginal edges of the center portion of the stamping. These arm are inspaced relationship to one another and the marginal edge of the centerportion intermediate the bases of the arms is provided withsemi-circular cut-out portions or notches 4. Each arm is provided with aportion 5 adapted to form a vertically disposed wall 5 of the nut byThis stamping comprises a center being suitably bent upon a line 6. Theouter ends of the arms are provided with a portion I and which I termfingers, the outermost ends of which are curved as indicated at 8. Thefingers I are bent on the line 9 at right angles to the wall portion 50i the arms to form the nut top and the'. curved outer ends 8 of thefingers form an opening Ill which is an axial alignment with the opening2 in the bottom I I of the nut. The vertical faces of the ends 8 of thefingers are threaded as at I2 for the reception of the same bolt whichthreaded passes through the bottom bolt opening 2.

The' nut formed from the blank A is illustrated as being hexagonal butit is to be understood that it could be of other shapes and is notlimited t: a six-sided nut. The center portion I of the blank forms thenut bottom II and this bottom is depressed so that the bottom slantsdownwardly and outwardly as at I3 from the bolt opening 2 towards thelower ends It of the side wall. As a consequence when the nut isthreaded upon the shank I5 of a bolt 0 and positioned against a plate orplates I6 and H which are above the bolt head I8 as illustrated in 3 ofthe drawings, there is a space I9 between the nut bottc'n and the plateE6, the purpose of which will be later described.

By reference to Fig. 2,it will be seen that, in

its completed form, the side walls 5 of the nuthave attachment with oneanother only through the nut bottom I I. The vertical edges of each sidewall are separated from the opposing edges of an adjacent side wall by avertically extending slot 20 the lower end of which terminates in theaforementioned semi-circular notch 4 at the peripheral edge of thenutbottom I I. Each of the fingers I are similarly independent of oneanother as their opposing edges are separated by a continuation of theslots 20, which for clarity of understanding are designated 2|.

A practical-application of the nut and the looking action thereof isillustrated in Figs. 3 and 4. When the nut has beentumed down to theposition illustrated in Fig. 3 of the drawings clamping action is aboutto be exerted upon the plates or members I8 and Il. The outer peripheraledge I4 of the nut bottom has engaged the uppermost plate [6. A furtherand final tightening down of the nut results in the action illustratedin Fig. 4 .of the drawings. The depressed or concaved bottom II of thenut has been straightened or I flattened and the entire area of the nutbottom is in engagement with the. uppermost plate I6. Straightening thenut bottom causes the side walls I of the nut to be deformed inwardly asat 22 and causes the tongues I to move horizontally inward toward theshank I! oi the bolt. To the extent that the fingers I can move inwardlythe size of the upper bolt opening it formed by these fingers isreduced. The bolt shank will however permit only a very limited inwardmovement of the fingers notwithstanding an ever increasing inwardpressure caused by tightening down the nut. .As the nut istightened downthe ends 8 o! the fingers engage the bolt' shank under a progressivelyincreasingpressure, which pressure is sumcient to lock the nut againstrotation other than through the application of intended manual force.The side walls of the nut remain bowed and exert what can well beexpressed as a resilient or spring action which tends at all times toforce the ends of the fingers tightly against the bolt shank.

The nut bottom might not under all conditions of use andoperation beentirel straightened or flattened out but even when the bottom is onlydrawn partially down to meet the plate or abutment iii the lockingaction will still take place between the nut fingers and the bolt shankand this locking action will differ only in degree from the complete andfullest locking'action illustrated in Fig. 4 of the drawings.

Threaded bolts and nuts are manufactured with diflerent degrees ortolerances of clearance in their threads. The present lock nut makes itpossible to use threads having large clearance tolerances whereheretofore small thread clearance tolerances have had to be used toattain the desired results. The reason for this is of course due to theinward movement and pressure exerted upon the fingers 1 which results ina reduction oi the size of the upper nut opening it. This advantageis.also attained by the hereinafter described modified forms of theinvention.

'A modified form or the invention appears in Figs. 5 and 6 of thedrawings wherein the nut A is of the identical construction hereinbeforedescribed but a filler block or disc D is used in combination therewith.The filler disc is of the proper size and configuration to fit withinthe hollow nut and would of course be properly positioned upon the nutblank central portion I, that is, the nut bottom ll, before the fingersI are bent downwardly to extend across and form the top of the nut.

The block or insert is provided at its outer edge with three grooves orehannelways 23 and centrally is provided with an opening 24 for thereception of the bolt shank. Three grooves or channelways 25 extendradially from this center opening. When the disc or insert is within thenut the grooves or channelways 23 and 25 are positioned intermediate theslots or channelways' 20 and II between the nut fingers I. That is tosay, one each of the grooves 23 or 25 will be positioned below a finger.The block or insert is composed of a suitable elastic material and fibrehas been found to be very suitable as a material. The

central opening 24 of the insert is of a smaller diameter than the boltopenings 2 and ill of the nut and of smaller diameter than the shank ofthe bolt, as clearly appears in Fig. 6 of the drawings.

The opening 24 of the insert is threaded by the tion or the nut to thebolt. There is the locking action obtained by the side walls of the nutbeing deformed or bowed inwardly as has been described. The secondlocking action is that exerted by the fibre insert being forced tightlyagainst the bolt shank as a result of the inward bowing of the nutwalls. When the nut walls are bowed inwardly the fibre insert issqueezed or compressed and the side wall of the insert bolt receivingopening 24 is forced under pressure against the bolt shank. To theextent that it 11-. possible the diameter of the threaded opening cutthrough the insert by the bolt is reduced. The pressure engagementbetween the insert and the bolt shank is maintained as'has been pointedout when the operation of the nut illustrated in Figs. 1 to 4 aredescribed. The channel-ways or grooves 23 and 25 in the fibre insert arefor the purpose oi! facilitating the described compression of the insertwhen the side walls of the nut are deformed inwardly.

From the foregoing description it will be seen that the fingers Ioperate as clamping jaws and that when the fibre insert is used it alsotightly clamps the bolt. The nut as a consequence can quite properly bereferred to as having a "collet action.

The nut illustrated in Fig. '7 or the drawings is quite similar to thatheretofore described. It comprises a base or bottom 30 and being squareor rectangular in configuration has only two side walls 3| and 32. Thenut top is formed by a pair of fingers or jaw-like segments 33 and 34the ends of which stop short of one another as indicated at 35. The'nutbottom is provided with a threaded opening and extending oppositelydisposed ears 3'! provided with openings 38 for the reception of rivetsor some other suitable fastening means for securing the nut to a plate39 or the like. Should it be desirable the ears could be welded to theplate 39.

The opposing and separated ends of the fingers are provided with areshaped cut-out portions to provide an internally threaded upper boltopening 40 which is in axial alignment with the bolt opening 36 of thenut bottom.

The nut is made of deform-able sheet metal and like the previouslydescribed nut can be used with or without an insert disc or block. Thenut is illustrated as being used in combination with an insert Ecomposed of fibre or some other suitable resilient material.

The insert has a central portion 4| of the proper size and configurationto fit within and fill the hollow interior of the nut. At each end theinsert is provided with a head 42 which has ends extending beyond thesides 43 of the main insert portion 4| to provide shoulders 44 adaptedto abut the side edges 45 of the nut walls ii and 32 and to thereby lockthe insert against endwise movement. Cross-wise movement of the insertis prevented by the side walls of the nut. Centrally the insert isprovided with an opening 46' for the reception of the shank i5 of thebolt C. The diameter of this opening is less than that of the bolt shankand is threaded when the threads are out in the bottom opening 36 andthe finger or jaw ends. The slots 41 extend from opposite sides of theinsert bolt opening 46 and are cut through the entire thickness of theinsert.

The nut bottom 30 is depressed to make it concave as indicated at 48 toleave a space 49 between the nut bottom and the plate 39 to which it isattached by the nut ears 3'I.

From the description heretofore given the operation of the lockingaction of the nut to prevent rotation of the bolt will be understood.This locking action is illustrated in Fig. of the draw ings where itwill be seen that as the bolt is rotated to clamp the plate or element50 against the plate or element 39 the bolt bottom 30 is straightenedout so that its entire area engages the upper face of the plate 39. Thestraightening or flattening of the nut bottom deforms the side wallsinwardly-so that they are bowed as indicated at M. This forces thefingers or laws 33 and 3| inwardly into close engagement with the boltshank as has been hereinbefore described. This clamping or lockingaction takes place irrespective oi v fibre or resilient inserts D and Ein their bottom faces and surrounding their .respective bolt openings 2tand 46 are provided with a seat for the reception of the said flange 52.This construction provides for proper and rapid positioning of theinsert with its bolt opening in proper alignment with the bolt openingsof the nut.

It -is to be understood that the grooves in the inserts need not bepositioned exactly'as illustrated nor need they extend entirely throughthe inserts. The grooves nould also be greater or less in number.

I claim:

i. A device of the character described comprising, a deformable hollowsheet metal nut having a bottom, side walls and a top, said bottom beingprovided with a threaded opening, said top comprising a plurality ofjaws forming a threaded opening in axial alignment with said bottomopening, said openings being for the reception of a threaded bolt, aninsert composed of elastic material positioned within said nut and heldagainst rotation therein, said insert being provided with a threadedopening of like diameter to thatof the opening in the nut bottom, theopening of the insert being positioned in axial alignment with both ofthe nut openings, and the bottom 01' the nut being concaved for thepurpose described.

2. A device of the character described comprising, a deformable hollowsheet metal nut having a bottom with side walls at opposite sidesthereof, said bottom being concaved and centrally provided with anopening, atop for said nut composed of a pair of jaws extending inwardlyfrom said side walls and having their ends stopping short of oneanother, the opposing ends of said jaws being provided with threadedportions forming a threaded opening in axial alignment with the threadedopening of said nut bottom, said nut having oppositely positioned opensides, an insert composed of elastic. material positioned within saidnut and held against rotation therein, said insert engaging the verticaledges of said nut side walls and holding said nut against displacementthrough the open sides of the nut, and

said insert being provided with a threaded opening in axial alignmentwith and of like diameter to the threaded opening in saidnut bottom.

3. A construction as defined in claim 2 wherein, said insert is providedwith cut out portions constituting slots extending from and incommunication with opposite sides of its opening.

4. A device of the character described comprising, a deformable hollowsheet metal nut having a bottom, side walls and a top, said bottom beingprovided with a-threaded opening, said top comprising a plurality ofJaws forming a' threaded opening in axial alignment with said bottomopening, said openings being for the reception of a threaded bolt, thebottom of said nut being concaved, an insert composed of elasticmaterial positioned within said nut and held against rotation therein,said insert being provided with an opening of like diameter to that ofthe opening in the nut bottom, the opening of the insert beingpositioned in axial alignment with both of the nut insert and extendingradially from its opening and being positioned intermediate the slots ofsaid side walls.- r

I RAYMOND G. OLSON. J R.

